Analysis of Social Vulnerability Index of Portland City

Aung Myo Htut

2024-08-07

INTRODUCTION

The Social Vulnerability Index (SVI), developed by the Centers for Disease Control and Prevention’s Agency for Toxic Substances and Disease Registry (CDC/ATSDR), is a tool designed to identify communities at increased risk during public health emergencies. Understanding social vulnerability allows policymakers, emergency response planners, and public health officials to allocate resources and interventions more effectively, ensuring that those who are most in need receive appropriate support.

WHAT IS SOCIAL VULNERABILITY?

Every community must prepare for and respond to hazardous events, whether a natural disaster like a tornado or a disease outbreak, or an anthropogenic event such as a harmful chemical spill. The degree to which a community exhibits certain social conditions, including high poverty, low percentage of vehicle access, or crowded households, among others, may affect that community’s ability to prevent human suffering and financial loss in the event of a disaster. These factors describe a community’s social vulnerability.

THEMES AND CALCULATIONS

The SVI ranks each census tract on 16 social factors, grouped into four related themes, each representing a different aspect of social vulnerability:
Socioeconomic Status:

  • This theme includes indicators such as poverty, unemployment, housing cost burden, no health insurance, and no high school diploma.

Household Characteristics:

  • This includes metrics related to age (over 65 and under 17 years), disability, single-parent households, and English language proficiency.

Racial and Ethnic Minority Status:

  • This theme assesses the proportion of all racial/ethnic minorities other than Non-Hispanic Whites.

Housing Type and Transportation:

  • Indicators like multi-unit structures, mobile homes, crowding, no vehicle access, and group quarters are included, highlighting potential barriers in evacuation or shelter-in-place scenarios.

For each theme, the SVI uses U.S. Census data to score and rank each tract relative to others, considering these factors collectively to identify areas with potentially greater challenges during emergencies. Percentile ranking values range from 0 to 1, with higher values indicating greater social vulnerability.

Picture:SVI Themes

USAGE OF SVI

SVI can be used to:

  • Assess community need during emergency preparedness planning
  • Estimate the type and quantity of needed supplies such as food, water, medicine, and bedding.
  • Decide the number of emergency personnel required to assist people.
  • Identify areas in need of emergency shelters.
  • Create a plan to evacuate people, accounting for those who have special needs, such as those without vehicles, the elderly, or people who do not speak English well.
  • Identify communities that will need continued support to recover following an emergency or natural disaster.

TABLE OF SOCIAL VULNEARBILITY INDEX INDICATORS

Total
(N=20)
Overall SVI Ranking
Mean (SD) 0.633 (0.208)
Median [Min, Max] 0.665 [0.221, 0.957]
% of Persons Aged 17 & Younger Estimate
Mean (SD) 13.7 (6.09)
Median [Min, Max] 15.0 [3.90, 22.8]
% of Persons age 65 & Older Estimate
Mean (SD) 17.1 (7.70)
Median [Min, Max] 16.3 [4.30, 37.3]
Occupied Housing Units with More People than Rooms % Estimate
Mean (SD) 1.49 (1.69)
Median [Min, Max] 0.900 [0, 7.00]
Civilian Population with a Disability % Estimate
Mean (SD) 13.8 (5.97)
Median [Min, Max] 13.2 [5.30, 31.1]
% of Persons in Group Quarters Estimate
Mean (SD) 3.07 (3.60)
Median [Min, Max] 1.25 [0, 14.1]
% of Housing Cost-Burdened
Mean (SD) 32.2 (7.80)
Median [Min, Max] 31.0 [20.5, 53.2]
Persons with limited English speaking % Estimate
Mean (SD) 2.50 (2.33)
Median [Min, Max] 1.65 [0, 8.20]
% of Minority
Mean (SD) 18.1 (8.04)
Median [Min, Max] 17.7 [8.20, 34.8]
% of Mobile Homes Estimate
Mean (SD) 0.320 (0.711)
Median [Min, Max] 0 [0, 2.60]
Housing with 10 or more Units % Estimate
Mean (SD) 21.9 (18.4)
Median [Min, Max] 15.5 [0.400, 73.5]
Persons (age 25+) with No High School Diploma % Estimate
Mean (SD) 4.98 (3.01)
Median [Min, Max] 3.80 [1.60, 10.8]
Households with No Vehicles % Estimate
Mean (SD) 16.2 (10.5)
Median [Min, Max] 12.4 [2.90, 43.2]
% of Persons below 150% Poverty Estimate
Mean (SD) 20.2 (8.35)
Median [Min, Max] 18.7 [6.50, 42.9]
% of Single-Parent Households with Children Under 18 Estimate
Mean (SD) 4.08 (3.27)
Median [Min, Max] 3.30 [0, 12.3]
Unemployment Rate Estimate
Mean (SD) 3.71 (2.68)
Median [Min, Max] 3.15 [0.600, 12.0]
Total Civilian Population with Insurance % Estimate
Mean (SD) 6.34 (3.11)
Median [Min, Max] 5.95 [2.00, 12.0]

SOCIAL VULNERABILITY INDEX OF PORTLAND CITY

OVERALL SOCIAL VULNEARBILITY INDEX

AGE 17 & YOUNGER

AGE 65 & OLDER

CROWDING

DISABILITY

GROUP QUARTER

HOUSING COST BURDEN

LIMITED ENGLISH SPEAKING

MINORITY

MOBILE HOMES

MULTIPLE UNITS

NO HIGH SCHOOL DIPLOMA

NO VEHICLE

BELOW 150% POVERTY

SINGLE PARENT

UNEMPLOYMENT RATE

UNINSURED POPULATION

REFERENCES
CDC/ATSDR SVI
CDC SVI Documentation 2022